The twintube shock absorber is the most popular option for vehicle manufacturers, with roughly 85% of cars using this technology from OE. As the name suggests, it contains both an inner and an outer tube. They contain both oil and pressurised gas. The required resistance is created by the oil passing from inner to outer tube through a number of carefully calibrated valves.
During vigorous driving or extreme road conditions, the pressurised gas in the outer cylinder can mix with the oil, creating aeration and reduced performance. If you or your customer is likely to drive under these conditions, we recommend upgrading to a monotube.
The monotube shock absorber has just 1 big cylinder, instead of 2. Gas and oil is physically separated by a floating piston, eliminating the risk of aeration. The 1 big cylinder allows for a much bigger piston valve, providing a wider area of pressure and a more precise damping force. This gives the car a sharper, more responsive drive, perfect for performance cars.
Take a look at them both in action in the above video.